Yeast



Patented May 27, 1941 UNITED STATES PATENT' OFFICE 2,243,129 mas! AlfredS. Schultz, Bronx, N. Y., assignor to Standard Brands Incorporated, NewYork, N. Y., a

corporation of Delaware No Drawing. [Application June 16, 1937, SerialNo. 148,509

.10 Claims. (CL 99-96) The invention relates to a process for theenrichment of yeast in vitamin B1, and more particularly to thepreparation of a vitamin B1 containing extract and its utilization inthe treatment of yeast. It includes correlated improvements anddiscoveries whereby the vitamin B1 content of yeast may be enhanced.

An object of the invention is the provision of a process in which thevitamin B1 content of a yeast may be markedly increased in a ready andeffective manner.

Another object of the invention is to provide a procedure for theobtainment of an extract rich The invention accordingly comprises thesev-:

eral steps and the relation of one or more of such steps with respect toeach of the others, and the composition possessing the features,properties,

and the relation of. constituents, which are exemplified in thefollowing detailed disclosure.

In the practice of the invention, the vitamin B1 content of yeast,especially bakers yeast, may be augmented by subjecting the yeast to theinfluence of an aqueous extract of unsaccharified rice polish and ricebran. Suitably the extract is obtained by treating rice polish and ricebran in admixture with water, adding ammonia thereto, and after a givenperiod adjusting the acidity to a pH value of 3.8 to 5. The ammoniacalwater utilized for the extraction of the rice polish and rice bran maydesirably have a pH value of about 7 to 8, more particularly of 7.5. Theacidification may be accomplished through the addition of a mineralacid, as sulfuric, hydrochloric and phosphoric.

The extract containing vitamin B1 may be utilized for increasing thevitamin B1 content of yeast by subjecting yeast to the influencethereof. Thi may be carried out by placing the yeast in the extract at apH of about 5.0, and allowing it to remain therein for a period of time,suitably one hour at room temperature and with frequent stirring. At theend of this period the yeast may be removed and the treatment repeatedas long as the operation is emcient.

In addition to the foregoing method'of treatment subjection to theinfluence of the extract may be brought about by introducing the extractinto the wort or mash in which yeast is grown. This addition may be madeat any period throughout the growth of the yeast, or it may follow thegrowth period by introducing the extract into the fermenter andpermitting the yeast to remain in contact therewith. These procedureslead to a marked increase in the vitamin B1 content of yeast. We havereadily succeeded in reaching a potency of approximately 120International units of vitamin B1 per gram under commercial conditions.The medium employed for treatment of the yeast which contains an extractof unsaccharified rice polish and rice bran, preferably an ammoniacalaqueous extract, may have a pH value of from 3.8 to 5.0, and if thevalue isother than about 5, it is so adjusted for the treatment of yeasttherewith.

In the production of the extract, substantially equal amounts of therice polish and rice bran are utilized and the ratio of ammoniacal waterbe 1 to 10, or 1 to 5, depending as to whether a higher or lowerconcentration is deemed to be desirable. The initial extraction isefiected with the ammoniacal water, and after a short period, aboutfifteen minutes, acidification is effected by introducing an inorganicacid, such as sulfuric acid, with the medium having a pH value of about3.8, and about 4.2.

Following acidification the solid is separated from the liquid whichcontains the vitamin B1, and this liquid may subsequently be sterilizedby means of heat and at a temperature of about C. The sterilization maygive rise to the formation of a slight precipitate, which may be removedby filtering. Further, the'sterilization may be carried out by heatingto about the boiling point, but when the liquid is thus heated there isobtained a white fiocculent precipitate, and prior to use thisprecipitate is removed by filtering.

As an illustrative embodiment, of a manner in which a vitamin B1 extractmay be produced from rice polish and rice bran and utilized for theenrichment of yeast, the following examples are presented.

Example I A mixture ofsubstantially equal parts of rice polish and ricebran, specifically 1,000 grams of rice polish and 1,000 grams of ricebran, are mixed with about. 18.6 liters of water. The admixture isstirred and concentrated ammonia added thereto in an amount of 25 cc. inorder to give a pH value of about '7 to 8. After iiiteen minutes thewort with the yeast to be tested, and also about 40 cc. of concentratedsulfuric acid are with a yeast and a given amount of synthetic added,lowering the pH value in the neighborhood crystalline vitamin B1. Theamounts or gas or 8.8. The mass is stirred and the solid and evolvedaredetermined and compared, and the B1 liquid then separated by filteringin any suitable content o i the prepared yeast thus ascertained.

manner. 'rh illiquid; gobtained may'QtheniQbej in eizanipige ptamed .asterilized"'by"-means o'iheat andsuitably at a InternatlonaLunit'oivitamin Brper'cc'. Since temperature or about 75 C. At this temperaturea total or four treatments, utilizing 3,000 cc. for little or noprecipitation will occur, but it the each treatment were made, theamount of exheating is continued to the boiling point a whiteyl, tractto which the yeast was subjected was 12,000 flocculent precipitate isformed which may be cc., and 1 2,000x .8 equals 9600 Internationalunits. easily removed by illtration;: j The extract so The-solids oithe: momma maybe considered obtained may have a pH va1ueoffronr--'3.8 to5, season} 100 'fand since the yeast, by the and a suitable value forthe extract for storage gadtestfshbwed tamin B1 content of 80 Interprpos is about When li ed; 19 1 netionai =,units in dry, the total amountof treatment of yeast the pH value may be adjust- 1 yeastroontained 8,..units, and hence the efed to about 5.0 by the addition of a suitablealilciencypi the processis about 80%. kali, as ammonium hydroxide, orcompounds 01* aodium andlpotassium.

Y eastof. etype-wedesignate An extract samemsrecaaantaaa thss. fled.rice polishebranfextract, and intojthe,.mi.x-. that produced by ExampleI may. beapreparedby ture'ithus obtainedi600a-cc :01: water --.werezintro-x;

mercial, were addedikto 500cc.- of. the vunsa cha'ri-.-i i

admixing 1,000 grams of rice. polish and .-,-1,000, duced.'=a..The pH-ot-Ethezextractwag*adiustedto grams of rice bran with 10 liters=oiwater, adding about 5.0 beiorerintermixturetavithi the yeast.-

thereto about 25 cc. otconcentrated ammonia, The .massawas;stirred-dor.:about: 15: minutes and and after standing for about.fliteenminutes intheniflltered. Thisiyeast was subiected toasectroducing about 40 cc. oisoncentrated sulfuric ond andthird treatmentof aT-similar nature, with acid. The mass is then filtered yielding aliquid the period of treatment lengthened .toabout one containingvitamin B1 in a volume of :about 6 hour. The yeast obtained was analyzedfor. solids, liters. The filter cake is now mixed withabout and'thendried;andathezvitamin-aB1-.content-de- 8 liters of water, and as aresult of a second ill-' termineda'f aregivenrbelowp I tration about 8liters of asecond'runextract are M obtained, making a total of14::1iters having a' v t m vitamin B1 potency as determinedby the gas if'5 5 5," method described in a copending application Ser- I .Grams yeastSolids 13 235573,;{3 2 23;? gm ial No. 141.278 equal to 80% or higher ofthe rice 1 .1 l g ggg polish. In the event that the acidity of the exw1mm" x tractistoo great, it maybecorrected by theaddi- L c r tion of analkaline substance, and if desired, the m Pear e? GMT; 6 i Pmu'w.extract may be concentrated by use of suitable g r evaporators. a 400co.) m. 1.. .1, Example III F--.--- J); r 3. 700

baker's yeast, diluting to 1 liter with water, and adding thereto 3liters of the rice polish-bran H i 3 a. extract obtained in accordancewith the fore- E 'sampleV that the procedure-is about emcient.

going examples, and which has a pH of about 5. 5o i m' fifi Should theextract have a pH value other than 5, it may be adjusted thereto by theaddition of a suitable acid or alkali as may be required. The yeast issubjected to the influence of the rice through utilization-ottheextract; or unsaccharifled riaepolishandrice .branzduring the grow-,,ingof yeast, or in the iermentenis shown by polish-bran extract forabout one hour at room the il '1 temperature, and withi'requentstirring. I B f Thereafter about 8 liters of water may be M Ias v ifl'fiifi added, and the entire mixture separated by Bead f' P 8duemeans or a yeast separator. The cream yeast so r f, 1 13;. .f fij,obtained, havingavolume of 1.5to21iters,isnow m ,1. incorporated withabout 3 liters of the rice polish- Gram I bran extract having a pH 0!about 5.0, allowed g9,

to re a n for one hour, d p t Thi sIIIIZIZ :00 21212121221121 "so s m.procedure may be repeated, for example, two We Y more times, thllssubjecting the yeast to the in- Llkg a :00 1n is v iluence of aplurality of portions of the aqueous 141M" if 5' fj 9 .2 extract fromthe rice polish and bran. Alter the successive treatments the creamyeast is di- The x r t in r ced ls thatwhich m y b luted to about 12liters with water, separated, p p y Examples I and [H y rea ment of thusgiving it a washing, and finally it is filtered; 7o rice polish and ricebran with ammoniaeai water Following filtration the yeast is dried at atemat a pH of about 7.5, acidification with sulfuric perature of 30-35(2., and the vitamin B1 conacid with separation of solid.andliquid,and-;obtent determined by the .gas method. This tainment of anextracthaving a pH value-oi. th briefly, t il th preparation of a,gynabout 4.2. The pH at the completion of each thetic sugar wort, andinoculating a portion of fermentation was set at about 4.5 to 5.2.

It will be noted that there is a marked increase in the vitamin B1content of the yeast which is subjected to the influence of the ricepolish-bran extract during its growth. Thus, the type 1 yeast gave anincrease of 685 units, type 2 yeast an increase of 646 units, and type 3an increase of 915 units. On the basis of 1,000 units in the extract,the efficiency is about 65% for the type 1, and the type 2 yeast, andabout 90% for the type 3.

The' foregoing procedures provide a medium rich in vitamin B1, andobtained by an ammoniacal water extraction of rice polish and rice bran,which is well adapted 'for the treatment of yeast. The treatment ofyeast therewith, at a suitablepH value, either before or after growingor propagation, leads tothe obtainment of a yeast of distinctly highervitamin B1 content. The efliciency of the procedure is decidedly highand may reach 90% in the case of a type 3 yeast. Thus, there is provideda ready, effective and economical manner whereby the vitamin B1 contentof yeast may be augmented without decrease in yield of the yeast andwithout undesirable effects upon the yeast, either as to bakingstrength, keeping qualities, or color.

Since certain changes in carrying out the above process, and certainmodifications in the composition which embody the invention may be madewithout departing from its scope, it is intended that all mattercontained in the above description shall be interpreted as illustrativeand not in a limiting sense.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. A process for preparing a composition containing vitamin B1, whichcomprises extracting a mixture of rice polish and rice bran withammoniated water, acidifying to a pH value of 3.8 to 5, and separatingsolid from liquid whereby a liquid rich in vitamin B1 is obtained.

2. A process for preparing a composition containing vitamin B1, whichcomprises extracting a mixture of rice polish and rice bran withammoniacal water at a pH value of 7 to 8, acidifying to a pH value of3.8 to 5, and separating solid from liquid whereby a liquid rich invitamin B1 is obtained.

3. A process for preparing a composition con- 'taining vitamin B1, whichcomprises extracting a mixture of rice polish and rice bran withammoniacal water at a pH value of 7 to 8, acidifying with sulfuric acidto a pH value of 3.8 to 5, separating solid from liquid whereby a liquidrich in vitamin B1 is obtained, and sterilizing the liquid.

4. A process for preparing a composition containing vitamin B1, whichcomprises extracting a mixture of rice polish and rice bran withammoniacal water at a pH value of 7 to 8, acidifying with sulfuric acidto a. pH value of 3.8 to 5, separating solid from liquid whereby aliquid rich in vitamin B1 is obtained, and sterilizing the liquid byheating to a temperature of about C.

5. A process for preparing a composition containing vitamin B1, whichcomprises admixing rice polish and rice bran with water, adding aqueousammonia to a pH value of about 7.5, acidifying by means of sulfuric acidto a pH value of about 4.2, separating solid from liquid whereby aliquid enriched in vitamin B1 is obtained, and sterilizing the liquid byheating to a temperature of about 75 C.

6. A process for preparing a composition containing vitamin B1, whichcomprises admixing rice polish and rice bran with water, adding aqueousammonia to a pH value of about 7.5, acidifying by means of sulfuric acidto a pH value of about 4.2, separating solid from liquid whereby aliquid enriched in vitamin B1 is obtained,

sterilizing by heating the liquid thus obtained until a white flocculentprecipitate is formed, and removing precipitate so produced.

7. A process for preparing a composition containingvitamin B1, whichcomprises admixing rice polish and rice bran in substantially equalquantities with water, adding aqueous ammonia to a pH value of about7.5, acidifying with sulfuric acid to a pH value of about 4.2,separating solid from liquid whereby liquid enriched in vitamin B1 isobtained, and sterilizing by means of heat.

8. A process for increasing the vitamin B1 content of yeast, whichcomprises placing yeast in a medium containing an aqueous extract ofunsaccharified rice polish and rice bran at a pH of about 5, allowingsaid yeast to remain therein for a period of time with agitation at roomtemperature, and separating yeast from said medium.

9. A process for increasing the vitamin B1 content of yeast, whichcomprises placing yeast in a medium containing an aqueous extract ofunsaccharified rice polish and rice bran which has been heated to atemperature of about 75 C. and cooled, at a pH of about 5, allowing saidyeast to remain therein for a period of from 15 minutes to one hour withagitation at room tem perature, and separating yeast from said medium.

10. A process for increasing the vitamin B1 content of yeast, whichcomprises preparing an acidified ammoniacal aqueous extract ofunsaccharified rice polish and rice bran, inoculating a mediumcontaining said extract and having a pH of about 5 with yeast, growingthe yeast therein, and separating yeast from said medium,

. ALFRED S. SCHULTZ.

